Along with the booming growth in the multi-media industry, the disc with smaller size, larger capacity and longer duration of data storage has won great popularity among consumers. Due to the popularity of the disc, the disc drive with disc access function is crucial to the multi-media market. Existing tray-type disc drive has a tray and a tray motor. The tray is used for carrying a disc, and the tray motor is used for driving the tray to enter or exit the disc drive, so that the user can conveniently load the disc into the disc drive or unload the disc from the disc drive.
Normally, when the user would like to unload the disc, the control unit of the disc drive provides a default ejection time within which the tray motor drives the tray to move, such that the disc can be unloaded from the disc drive. The setting of the default ejection time is based on whether the tray can stably and accurately exit the disc drive.
However, the way of setting a default ejection time within which the tray is driven to unload the disc from the disc drive does not guarantee that the tray can stably exit the disc drive or that the ejection distance of the tray can be controlled accurately. Therefore, when the user uses the disc drive, the tray may collide with the stopper and tremble heavily if the ejection distance is too long, or may have an insufficient ejection distance.
For example, if the power outputted from the tray motor is too small or the ejection time is too short, the tray cannot move to a default position, from which the user can conveniently unload the disc. Conversely, if the power outputted from the tray motor is too large or the ejection time is too long, the tray may collide with the stopper disposed on the base. Under such circumstance, the use efficiency of the disc drive will decrease dramatically. To the worse, if the tray exits the disc drive at a high speed and the speed cannot be timely reduced, the tray may easily collide with the stopper disposed on the base and tremble severely. Such trembling may cause the disc to come off the tray, and the disc may be damaged.
Also, to avoid huge collision between the tray and the base, existing disc drive activates the limit switch when the tray moves to be near the predetermined position, and further transmits a feedback signal to the tray motor to activate a braking function to avoid the tray exceeding the predetermined position and colliding with the base. However, the use of limit switch will incur more cost and parts to the disc drive, and cannot save production cost.